1. Field of the Invention
The present invention relates to a mixing apparatus for crushing sludge.
2. Background
In general, in order to remove floating matters contained in waste water and water through coagulation and sedimentation, a chemical (coagulant) is fed into the waste water and the like to cause a coagulation reaction.
Through the coagulation reaction, a flock is formed coagulated by a coagulant such as a particle of an organic matter and a microbe or a suspended material of the waste water and the like. For the flock formation in the precipitation tank, the thickener tank, and the like, the chemical (coagulant) is fed into a pipe or the chemical (coagulant) is fed separately into the precipitation tank, the thickener tank, and the like in general
In the case of the abovementioned typical method, raw water (sludge) and the chemical (coagulant) are not agitated appropriately, and the flock is formed insufficiently, which leads to an overfeeding of the chemical during the flock formation.
In the case of a belt press dehydrator for a sludge dehydration process, an agitator of a quadrangular agitation tank at a front rotates at a slow speed to carry out agitation. In this case, sufficient time is not provided for the raw water (sludge) and the chemical (coagulant) to react with each other, and sizes of the formed flocks are irregular and large, hindering an even distribution at the belt press dehydrator.
Also, adequate agitation is unlikely while the flock stays in the agitator, which leads to the overfeeding of the chemical during the dehydration process. Therefore, a filter cloth is clogged, water filtering performance is lowered, and an increase in water content becomes unavoidable.
A centrifugal dehydrator feeds the chemical by connecting a raw water (sludge) pipe leading to the belt press dehydrator with a chemical (coagulant) pipe. A simultaneous feeding into the belt press dehydrator is made, and the flock formation and dehydration is conducted by a turning force of the centrifugal dehydrator. Since the coagulation reaction is carried out in the belt press dehydrator, the reaction is made inadequately before discharge, meaning that the water content is maintained higher than a design value during operation, and operation efficiency of the dehydrator drops due to the flock formation based on the overfeeding of the chemical
The problem to be solved by the present invention is to provide a new mixing apparatus for crushing sludge, preferably installed at a raw water (sludge) pipe to mix raw water (sludge) with a chemical (coagulant) in a precipitation tank, a thickener tank, a thickener, and a dehydration process at a filtration plant, a waste water disposal plant, etc.
This problem is solved by a mixing apparatus according to claim 1. Advantageous and/or preferred embodiments can be obtained from the dependent claims.
In particular, a mixing apparatus for crushing sludge according to the invention may include a motor part in which a rotary shaft is inserted into the motor part and the motor part is rotated, a moving part formed to penetrate the motor part from one side to another side and move a chemical which is flowed through an outside chemical feeder to the another side, and a paddle mounted on the another side of the motor part to rotate based on the rotation of the motor part and spray the chemical.
The paddle may have a moving hole which the chemical moves inside, a discharge hole connected to the moving hole and discharging the chemical outside, and a saw-toothed part projecting outside.
An inner wall surface of the discharge hole and a corner of the saw-toothed part of the paddle may be formed sharply.
The motor part may include a main body in which the rotary shaft is inserted into the main body, a first plate combined with one side of the main body and one outer circumference of the shaft, and a second plate combined with another side of the main body and another outer circumference of the shaft.
The shaft may have a penetrating path inside to move the chemical fed at one side to another side.
The first plate may include a first bearing part combined with an outer circumference of the shaft, a first sealing part combined to surround the first bearing part, and an inlet part formed in the first sealing part and allowing the chemical fed from outside to flow to a penetrating path of the shaft.
The first sealing part may be a mechanical seal.
The second plate may include a second bearing part combined with an outer circumference of the shaft, a second sealing part combined to surround the second bearing part around an outer circumference of the second bearing part, and a securing part surrounding the second bearing part and the second sealing part, and securing the second bearing part and the second sealing part to the another side of the motor part.
The second sealing part may be a mechanical seal.
The moving part may include an inlet part formed on the first plate and allowing the chemical to flow in, a penetrating path formed in the shaft of the motor part, and a moving hole formed in the paddle.
The mixing apparatus may be installed, in particular vertically, at a raw water (sludge) pipe to mix raw water (sludge) with a chemical (coagulant) in a precipitation tank, a thickener tank, a thickener, and a dehydration process at a filtration plant, a waste water disposal plant, etc.
According to the present invention, dehydrator efficiency is raised and water content of a dehydration cake is lowered since a microbial cell is destroyed by a corner of a saw-toothed part of a rotating paddle while cavitation is induced to remove moisture contained in the microbial cell.
Further, since agitation is conducted by the paddle rotating at a high speed in a narrow pipe, an even and solid flock is made by using a proper amount of chemical (coagulant) so that the chemical (coagulant) is saved compared to a previous chemical (coagulant) feeding method. Sludge sedimentation and thickening efficiency improves, and overall efficiency of water purification and waste water treatment increases.